Ultra-fine particles or nanoparticle (particles having an average diameter of 200 nanometers or less) are believed to be useful in the fabrication of microelectronic devices. Alivisatos et al., in U.S. Pat. No. 5,262,357, describe a method for making semiconductor nanoparticles from semiconductor precursors. Alivisatos et al. describe using these semiconductor nanoparticles to make continuous semiconductor films. Because the semiconductor nanoparticles exhibit significantly lower melting temperature than bulk materials, a layer of the semiconductor nanoparticles can be deposited on a substrate and annealed at relatively low temperatures, whereby the nanoparticles melt to form a continuous film.
One of the goals for nanotechnology is to develop techniques and materials that will allow for the fabrication of microelectronic devices on a variety of substrates using selective deposition, printing and/or imaging technologies. These selective deposition, printing and/or imaging technologies can utilize nanoparticles, or inks comprising nanoparticles, to fabricate layers in microelectronic devices.
There have been recent efforts to make metal-based solutions, which can be used to make conductive device layers in the fabrication of microelectronic devices. For example, Kydd in U.S. Pat. No. 5,882,722 describes a method of forming conductive layers from a suspension of mixtures of a metal powder and an organometallic compound dispensed in an organic solvent. The suspension is deposited onto a substrate to form a layer. The layer is then cured to form the conductive layer.
One of the shortcomings of fabricating thin conductive layers with liquids comprising metal-based materials, such as described above, is that the layers tend to exhibit poor adhesion and delaminate from the substrate and/or form irregularities during and/or after the curing process. Further, there is a tendency for hillock formation and/or pin hole formation during and/or after the curing process. Therefore, there is a need to develop suitable substrates and/or methods for depositing, printing and/or imaging liquid metal-based materials, which provide improved adhesion and reduced topographical irregularities in the resultant films during and/or after the curing process and which can be used to form active device layers in the fabrication of microelectronic devices.